Segment Information - Reported Revenue and Profit Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue
Total revenue	$ (234,530)	$ (213,261)
Income (loss) before income taxes
Income (Loss) before income taxes from continuing operations	9,625	(7,025)
Private Client Division
Revenue
Total revenue	(154,094)	(137,389)
Income (loss) before income taxes
Income (Loss) before income taxes from continuing operations	$ 40,162	28,762
Asset management fees	90.00%
Asset Management
Revenue
Total revenue	$ (17,644)	(18,666)
Income (loss) before income taxes
Income (Loss) before income taxes from continuing operations	$ 3,718	3,711
Asset management fees	10.00%
Capital markets
Revenue
Total revenue	$ (61,529)	(55,903)
Income (loss) before income taxes
Income (Loss) before income taxes from continuing operations	(6,057)	(12,614)
Corporate/Other
Revenue
Total revenue	(1,263)	(1,303)
Income (loss) before income taxes
Income (Loss) before income taxes from continuing operations	$ (28,198)	$ (26,884)